Scott Kim calls anything that can be read in more than one way an "inversion."

He used such writing in developing new font systems for computers.

Graphic artist John Langdon of Philadelphia, has developed writing similar to Kim's that he calls "ambigrams."

Artist M. C. Escher used many types of symmetries in designing his famous tessellations.

A circle and a sphere have the most symmetries of any geometric objects.

A figure with both horizontal and vertical lines of symmetry also has 180° rotational symmetry, but not the other way around.